Adam's Ordovician.

[Tidgy's Dad]

Here's another much larger Eoplectodonta rhombica. 

This is a lovely one, 2.5 cm wide. 

You can see the few widely-spaced primary costellae with lots of very fine parvicostellae in between them.   

Beak from reverse of rock. 

I adore it when i can find beautiful fossils in matrix pieces I've been sent. 

So, thank you so much, @Kasia for this and the specimens posted above. 

[Tidgy's Dad]

From the Lower Ordovician Fezouata Formation of the Zagora area, Morocco, this is a nodule containing the calyx of the rhombiferan cystoid Macrocystella. 

The rock is too hard to prep further.

 

 

 

 

 

 

 

[FossilDAWG]

Nice one!  I do like cystoids .

Don

[Malcolmt]

Very nice..I too am partial to cystoids

[Bobby Rico]

On 11/08/2020 at 3:50 PM, Tidgy's Dad said:

nyway, I got out my prepping pin, recently, and attacked i

Cute little bug my friend and you prepared to nicely. 

[Tidgy's Dad]

13 hours ago, Bobby Rico said:

Cute little bug my friend and you prepared to nicely. 

Thanks, Bobby.

It's a pleasure prepping gorgeous little fossils like this! 

[Tidgy's Dad]

On 9/3/2020 at 8:45 PM, FossilDAWG said:

Nice one!  I do like cystoids .

Don

 

On 9/3/2020 at 9:05 PM, Malcolmt said:

Very nice..I too am partial to cystoids

Thank you, chaps. 

Me too. 

And all the other weird echinoderms from the Palaeozoic. 

Not quite so weird, but here's a decent sized protasterid ophiuroid from near Tafilalt, Morocco. 

The scale is inches, but the disc is 3.2 cm in diameter and the longest arm 7 cm, probably 8 if completely straight and complete, so  I reckon this would have been a total of about 20 cm across.

 

 

 

 

[Malcolmt]

Very nice ... a shame these never preserve a lot of detail

 

[Tidgy's Dad]

Well, I started off this thread nearly three years ago with some graptolites.

So it seems nice to bookend it, for now, with graptolites.

My first from the USA. 

From the Galena Group, Upper Ordovician of Fillmore County, Minnesota, these are diplograptids,  maybe Amplexograptus maxwelli. 

 

 

Very nice. 

Thank you again to my friend Mike @minnbuckeye for these. 

 

And thank you again to all those who've looked, liked and licked these pages, plus all those who've commented and contributed specimens to Adam's Ordovician. 

My favourite Period, all done for now, but I hope to add to it one day. 

Back to Adam's Silurian for now, to continue the Wenlock; lovely. 

 

[Tidgy's Dad]

I have recently received my first fossils from the Middle Ordovician Salona Formation, Trenton Group of central Pennsylvania from the marvelous @Misha

These are Sowerbyella sp.

The largest one is 1.8 cm across.

Close up of some of the ones in the larger yellowish block : 

Brachiopods have layered shells and many of these specimens have part of the outer layer removed revealing details of internal shell morphology such as the pseudopunctate structures; calcite columns running through the inner shell layers.

Here is the best specimen from the biggest of the two grey shale pieces, 1.4 cm wide.

 

Another one : 

And one from the reverse of that shale piece, 1 cm across.

 

[Tidgy's Dad]

You can just see on the bottom left of that last photo, a bit of bryozoa. 

It's only a fragment, about a mm wide, of the rather pretty cryptostome Stictopora fenestrata. 

  

Another bryozoan fragment  or two:

And a solitary crinoid columnal.

Thanks again, @Misha

 

[Misha]

Wow! You were able to find some extraordinary details in those fossils that I wouldn't have even considered being there.

 

I will need to look at the samples that I've kept to see if anything like that shows up on them.

 

Otherwise, I'm glad you enjoyed the fossils!

[Tidgy's Dad]

 

2 hours ago, Misha said:

Wow! You were able to find some extraordinary details in those fossils that I wouldn't have even considered being there.

 

I will need to look at the samples that I've kept to see if anything like that shows up on them.

 

Otherwise, I'm glad you enjoyed the fossils!

Thanks, @Misha! 

I wouldn't be without my digital microscope these days! 

So thanks so much for that, Ralph @Nimravis

[Tidgy's Dad]

The marvelous @Monica has kindly sent me some further specimens from the Late Ordovician Georgian Bay Formation. 

Here are a couple of small bivalves, much smaller than some of the quite large modiomorphis or even Ambonychia which I posted earlier. 

Many of the bivalves in this formation look rather similar in shape but can be from quite different orders. And often they are preserved as internal moulds with very little detail preserved so identification is difficult or impossible. But these, especially one of them exhibit a little groove next to the hinge which may be where the clavicular ridge was on the outside of the shell which leaves a groove underneath it.  So, these may be a species of Clidophorus, possibly. 

This one, the larger specimen, has a shallow groove which doesn't show up very well in this photo.  

The groove is much clearer in these two smaller specimens, just to the right of the beak. 

Another shot :

[Tidgy's Dad]

This is the monoplacophoran Cyrtolites ornatus. 

It's a nice little fragment and is the oldest monoplacophoran I have, as the Bellerophontida are currently back in the Gastropoda again.

This photo just to show it in ordinary lighting, the fossil is 1.3 cm long :

Close up of detail :

 

[Tidgy's Dad]

And my very first scolecodonts! 

Scolecodonts are the tiny jaws of polychaete annelids. Worms with fearsome gnashers! Scolecodont isn't a taxon, it's just the name for these hard jaws. They actually belong to the Order Eunicida and can be from lots of different families and genera. The first appear at the very end of the Cambrian become common in the Middle to late Ordovician and are often found in numbers in Silurian deposits and some Devonian strata too. They are uncommon after this, but still exist today. 

Here is a modern one, the species Eunice aphroditois, from Indonesia those big jaws are what sometimes fossilize as conodonts :

Here is a nice Ordovician version that I've nicked from @GeschWhat. It's great, Lori.

The creatures actually had a whole set of jaws, external and internal for grasping, biting and aiding digestion. 

Here are the various bits from the genus Ramphoprion. (from Wiki) 

Monica sent me this piece from the Georgian Bay Formation, Late Ordovician. It is full of bits of conodonts which are the little shiny, black bits just about visible to the naked eye. The biggest one is 3 mm long, most are 1 to 2 mm or even less. 

This is the biggest one, which could be Ramphoprion sp. but these are very confusing to the untrained eye. 

And maybe these smaller bits are the same genus :

 

 

 

 

[Tidgy's Dad]

I think these ones are Protarabellites or more likely Oenonites sp. 2 mm or less.

Protarabellites used to belong to the family Arabellidae but the whole family were transferred into the family Oenonidae. The Oenonidae were then placed into the family Polychaetaspidae, which is where I think both species are at the moment. Very complicated, scolecodonts. 

 

 

 

 

[Tidgy's Dad]

Here are some other scolecodont bits, all very tiny indeed, 2 mm or less :

Two or three jaw sections that seem to be linked : 

Not sure if this is anything in particular : 

 

 

 

 

[Tidgy's Dad]

And also in this block were a little brachiopod, a Zygospira modesta, I think :

And a fragment of crinoid columnal, which are quite rare in the bits of Georgian Bay formation that I have in my collection. 

That's it for now, thanks again, Monica, beautiful pieces!  @Monica

[Monica]

@Tidgy's Dad

WOW, Adam!!!  You took some really nice pictures of these little pieces - well done!!! 

[Tidgy's Dad]

13 hours ago, Monica said:

@Tidgy's Dad

WOW, Adam!!!  You took some really nice pictures of these little pieces - well done!!! 

This digital microscope is a marvel.

Thanks, Monica. 

[GeschWhat]

Love the micro images, Adam. There is SO much to see in the micro world. It never ceases to amaze me! 

On 11/30/2020 at 8:48 AM, Tidgy's Dad said:

Here is a nice Ordovician version that I've nicked from @GeschWhat. It's great, Lori.

Nick away - a pleasure to be of service. 

[Tidgy's Dad]

Just now, GeschWhat said:

Love the micro images, Adam. There is SO much to see in the micro world. It never ceases to amaze me! 

Nick away - a pleasure to be of service. 

[Tidgy's Dad]

I have some more Ordovician fossils, all the following are thanks to my wonderful friend Ralph. @Nimravis

So, once again, a great big thank you, Ralph, there's some great stuff here.

First up, a nice chunky Vinlandostrophia ponderosa, maybe from Maysville, Kentucky.

Note the bumps along some of the central ribs, these are monticules of an encrusting bryozoa.

I like to compare the size to other similar forms such as this Vinlandostrophia laticosta also from the Maysville area. (Given to me by the much missed Doren) 

Here are some close ups of the bryozoan epibiont :

 

 

 

[Tidgy's Dad]

And a few more fossils for my much loved and growing  Lawrenceburg collection; a new species of bryozoan which has been on my wish list since I first saw them, and some nice Vinlandostrophia. 

The wonderfully spiky bryozoan is Parvohallopora ramosa and the longest bit measures 2.5 cm. 

Some pieces are anastomosing. (the colonies branch and then join up again.) 

Really beautiful detail  :